New research advances understanding of Parkinson’s disease stages

From a study that analyzed brain images of more than 2500 people with Parkinson’s disease in 20 different countries, scientists could identify patterns of neurodegeneration and create metrics for each of the five clinical stages of the disease.

The work published in NPJ Parkinson’s diseaserepresents a leap forward in the understanding of the disease. The analysis and the data obtained in the study can lead to important developments, not only in terms of diagnostic progress, but also in terms of making new treatments that can be tested and controlled like never before.

It is estimated that around 4 million people worldwide have Parkinson’s disease. It is a progressive neurological disease that influences certain structures in the brain, especially that related to movement. The progression of the disease is variable and differs from patient to patient, and it can take up to 20 years to go through all phases. In the initial phase there are the first signs are tremors, muscle stiffness and slow movements on only one side of the body. The symptoms then become bilateral. In the final phase, the patient depends on a wheelchair to make ends meet, because the stiffness in the legs prevents them from walking.

“Clinical diagnosis, supported by some additional tests, has been well established for many years. For the first time, however, it was possible to relate the degree of progression of the disease – the five stages of clinical symptoms – to quantitative changes in brain images,“Fernando Cendes, senior researcher at the Brazilian research institute for neuroscience and neurotechnology (Brasn) – a FAPESP Research, Innovation and Dissemination Center (RIDC), located at the state university of Campinas, in the state of São Paulo.

Brainin is one of the institutions that form the Enigma consortium, an international network that brings scientists together in imaging genomics, neurology and psychiatry to understand the structure and function of the brain based on magnetic resonance image formation with high resolution, genetic data, And other information from patients with epilepsy, Parkinson’s, Alzheimer’s, autism, schizophrenia and other neurodegenerative diseases.

Cendes explains that in Parkinson’s disease changes in the brain structure are of the so-called basic ganglia areas of the brain associated with automatic movement. The study, however, showed the existence of progressive changes in other cortical areas that were previously less involved in the disease.

We saw that as every phase of the disease progressed, there was a greater degree of atrophy or hypertrophy, not only in the movement -related structures, but also in other cortical areas. And it is these combinations of atrophy and hypertrophy related to the stage of the disease. “

Fernando Cendes, senior researcher at the Brazilian research institute for neuroscience and neurotechnology

“But that is not all we have observed, some of these structures also had differences in shape. They had changed their spatial configuration. Some regions of the Thalamus [a structure whose function is to relay information from the senses to the cerebral cortex] Was thicker. Other regions, such as the amygdalae [which play a role in regulating social behavior and emotions] had been atrophied“He notes.

The researcher explains that these changes cannot be seen with the naked eye: “They are submillimetric measurements. With programs and the use of artificial intelligence, however, it is possible to identify patterns and to check these changes in the future,“He says.

Push on new treatments

By setting up statistics to quantify brain changes related to the stages of Parkinson’s disease, the study could have various implications. Starting supporting a better diagnosis. “The morphometric data that we have obtained with this work are sensitive and reproducible measures with which we can support clinical diagnosis. With the wealth of data that we obtained in this study, it is possible, with the help of artificial intelligence, to make programs that help the clinic“He says.

Other developments are in the field of treatment. Currently Parkinson’s disease has no remedy, and only the lack of dopamine – a neurotransmitter that stops the neurons of Parkinson’s patients, the absence of which all brain changes and symptoms causes – is treated.

Over time, however, the disease is not limited to the basal ganglia, but also other areas of the brain ultimately influences dementia.

“The results of this work offer new ways to monitor treatments that can be developed in the future. The main objective with regard to the disease has been to find a treatment that stops the neurodegenerative process or at least reduces the speed of progression. And these measures that we have identified are essential for evaluating future therapies, to ensure that they work in a global way, not only in the brain areas related to movement, but also in the others who suffer, changes,“He points out.

A third impact of the study, which analyzes a large amount of data, is not in the field of medicine but in Data Science. “It is a very large cohort with different countries, study groups, stages of the disease and even types of data. So the innovation of the research is not only when identifying these statistics with regard to the stages of Parkinson’s disease, but also in all the work with regard to the data. The entire type of analysis used in the work was an important step forward for further studies using artificial intelligence and in other diseases,“Says Cendes.